Gravel Ridge Farms in Cullman, Alabama, recalled its cage-free large eggs last month saying the eggs could be contaminated. At the time, 14 people had been infected with the strain of Salmonella Enteritidis in Tennessee and Alabama.

Since then, the CDC has identified another two dozen illnesses from June 17 to Aug. 16, with some occurring in Colorado, Iowa, Kentucky, Ohio and Montana. Ten people have been hospitalized; no deaths have been reported, the CDC says.

The new cases bring the overall total to 38 people sickened across seven states, according to the CDC.

Salmonella causes about 1.2 million illnesses, 23,000 hospitalizations, and 450 deaths in the U.S. each year, the CDC estimates. Most people infected develop diarrhea, fever, and abdominal cramps within 12 to 72 hours.

The illness usually lasts 4 to 7 days, and most individuals recover without treatment. But some patients are hospitalized. The elderly, infants, and those with impaired immune systems are more likely to develop a severe illness from salmonella, the CDC says.

Gravel Ridge Farms sold the eggs in one dozen and 2.5 dozen cardboard containers to grocery stores and to restaurants primarily in Alabama, Georgia, and Tennessee. They were distributed between June 25 and Sept. 6, with "best if used by" dates of July 25 to Oct. 3 and the UPC code 7-06970-38444-6.